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Post by mrsonde on Apr 29, 2014 5:56:51 GMT 1
More waffle with no justification for any of your statements. The justification for my statements is in published scientific papers that together make the currently universally accepted Standard Model of the best physical explanation we have for how the universe works. Not a single part of that model requires or has any mention of the notion of "negative energy". Look for yourself. You're the one waffling, and making totally unsupported statements. You seem to believe because you can find someone else making the same equally unsupported statement this in some way provides evidence for them! I repeat: where's the theory, where's the maths, where's the measurements, where's the evidence?! You can't preovide any - because there isn't any. I've told you, it is not "generally accepted" at all. If it was, there'd be thousands of pages on the internet, from respected sources, quoting authoritative papers and research and confirmatory experiments. There would be links to the appropriate mathematical theories. There's none of that. All you can find is a yahoo answer, possibly from yourself for all I know, or at least someone equally as scientifically ignorant, and a "wow, isn;t the future fantastic" YouTube video. I understand you're talking nonsense. Else you'd be able to answer questions put to you, instead of blustering away with insults. The "rest of the physics community", as if you had the first clue about it, consider Mr.Hawking to be something of a publicity-hound and, at best, a second-rate theoretical physicist. Ffs! I've given you a widely respected source. I've given you the factual historical background. I can certainly quote from it, if you insist - but I fail to see why I should bother. Why don't you provide some evidence for your assertions? For once? Look - this is all the idea amounts to. Remove all the matter in the universe and you have a static gravitational field, according to GR. Introduce some matter, and you have a gravitational attraction; and of course it takes energy to accelerate any of that mass (either away from or towards that gravitational attraction, incidentally - pace Hawking's facile gibberish. That's it - that's all the idea amounts to. It's a metaphor. Nothing more. To elevate it into an ontological physical principle, so that "Gravity" is "Negative Energy" is absurd. At the very most, an eempty universal gravitational field has zero energy - but even then according to GR you've got to account for the tensors that make up its "pressure". Under no conditions is the energy content "negative" - the idea doesn't even make any sense! As current physical theory stands - universally accepted theory, and if you can find any physicist who says it's wrong, and is able to show why, then you've pointed to the next Nobel Prize winner, haven't you? On the other hand, if it is ever shown one day that anti-matter does react in a contrarywise manner to a gravitational field, then there may be cause to seriously consider the notion of "negative energy". But until that day arrives, there's not a single scrap of evidence for the idea. Is there?
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Post by nickrr on Apr 30, 2014 13:12:02 GMT 1
That you can make a statement like this after all the links I've posted speak volumes. Considering that you have failed to support any of your arguments displays a staggering level of hypocrisy.
Evidence please.
Then do so.
I'm having difficulty finding an expression that truly reflects the patent absurdity of this statement.
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Post by mrsonde on May 1, 2014 4:57:51 GMT 1
That you can make a statement like this after all the links I've posted speak volumes. All this blustering waffle is fooling no one. Even those who would like to agree with you must be despairing by now. Look - it's very simple. When you are asked to support your statements, statements that assert a hitherto totally unknown causal agent in the universe of immense power (it created the universe!) and incomparable significance (it maintains the energy balance in the entire universe; it accounts for its genesis; it purports to make any further hypothesis about creation superfluous; for just the obvious examples), then you're not being asked to merely post "links" to a couple of casual and unargued comments, whoever they might be from. It's incumbent on you to provide a link to the theory from which you derive your assertion - a scientifically published theory, with at the very minimum observational evidence accounted for and mathematical formulae linking it into existing findings and theory. That's called "science", see? Hang on - here's an off the cuff example that might make it clearer for you. A much less exotic form of novel energy, with drastically less a scope than your supposed variety: en.wikipedia.org/wiki/Cherenkov_radiationThat's just the wiki page entry - many times larger than the only one you could find, please note, with greater detail, observational reports, and mathematical implications. Goggle the subject and you'll find thousands of pages at whatever complexity you'd care for, including the original reports and theoretical papers. Let's see just an iota of that please, in your "links" that for some reason you believe supports your claims merely by the fact of repeating them. I have supported my arguments - I repeat, look at the contents of the Standard Model. Other than that, I've actually made my arguments - something you've conspicuously failed to do (other than having to resort to concepts solely applicable to 19th Century mechanics!) - and responded fully to what passes as yours (something you haven't been able to reciprocate either.) Evidence please that this is not true! My "evidence" was supplied in the recent Horizon documentary about him, when various physicists were asked to give him some sort of rank - that was the general view: not by any means in the forefront. Other than that, anyone with an awareness of the history of physics and its current state of development could tell you the same - his reputation far exceeds his actual achievements, for understandable reasons that have nothing to do with his contributions to science. Or then you could take the trouble to read anything he's written - a Penrose or a Susskind he's not. That he's a publicity hound is also clear from his theatrical behaviour - booking lecture halls to announce new "breakthroughs" (that turn out to be damp squibs), for example - which is also generally frowned upon by the physics community he lives amongst, even if it is California. For you? Why should I bother? Here's the first observation of it, though: en.wikipedia.org/wiki/Dmitri_SkobeltsynIn 1923. Years before Dirac's prediction. After that it had been detected twice in American cloud chambers. This is not to say it was identified as the "positron", of course - but it is to say it was only a matter of time, and would have been, based purely on those observations. Other than that, your argument is patently ludicrous. The accepted mathematical apparatus of physical theory has not arisen from nowhere, and it's not accepted for reasons of criteria internal to mathematics. It's arisen from experimental observation and logical reasoning; and any mathematical expressions that these then lead to are confirmed or falsified by further observations. Dirac formulated his equation - and predicted the positron - from considerations of existing observations that also led to Heisenberg's matrix mechanics and Schrodinger's wave equation, and by working through his philosophical intuition about the nature of the electron via the conditions of General Relativity (itself, a result of philosophical insight about the way the universe - the observable universe - behaved; and itself confirmed, by not being falsified, in clearcut observational tests of its implications.) Well - why don't you? Is it because you can't decide what the hell you mean by the term? Is it the difference between kinetic and potential energies when you do the sums right? Or is it anti-matter? Or is it gravitational attraction? So far you've made all three claims. And the only support for any of them is some glib remark in a popular science book saying because it requires work to pull masses apart gravity is negative energy! So, presumably, an electro-magnetic field is "negative energy" too, because of course charges can attract; and so is the strong nuclear force, and the weak nuclear force, and any bond, any exchange of particles. Given that reasoning, where every force we know is "negative energy", what the hell is "positive energy"? But frankly I've wasted enough time on this. Believe what you want. It's quite clear you haven't a clue what you're talking about, or how science works, or how to present a decent argument. Simply provide a link to the theory that you assert is "generally accepted" where its mathematical content has the quantity: -E, please. If not, you're not worth reasoning with, and you may have the last word.
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Post by nickrr on May 4, 2014 16:36:10 GMT 1
Ah, I see. To you, supporting your comments means making some vague hand-waving statement like "look at the contents of the Standard Model." No specific links of course. Whereas the various links that I've made to support my arguments (which incidentally themselves contain many further links to articles on the subjects) lead to accusations of providing no supporting evidence.
The quotation marks are entirely appropriate.
Well done - an attempt to support one of your arguments at last! It would have saved some time if you had just done this at the start.
Of course it would be interesting to know whether this had any influence on Dirac. My understanding is that Dirac predicted the existence of anti-matter based on his equations alone and only later was two-and-two put together. However I'm quite happy to be informed otherwise if there is evidence that these prior observations influenced him.
I'd disagree with the comment that the full nature of these particles would have been elucidated in time based on observations. All modern physics (all physics?) is only considered solved when we understand the maths behind it. Observations are just confirmations of the mathematical theory. The discovery of the Higgs boson is a case in point.
In any case it doesn't affect the original point that some branches of physics (quantum physics first comes to mind) are entirely about the maths, in that we can use the maths to predict quantum mechanical behaviour in great detail without having any idea what is really happening.
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Post by mrsonde on May 6, 2014 0:54:07 GMT 1
Ah, I see. To you, supporting your comments means making some vague hand-waving statement like "look at the contents of the Standard Model." No specific links of course. No specific links are possible, other than to the Standard Model, which I presume you're perfectly capable of googling yourself should the urge take you. There is no mention, or need or occasion to mention, "negative energy" in the Standard Model. Nothing to link to. That's the point. The links you've given are to off-the-cuff sweeping remarks in popular science books and YouTube videos. I repeat: this is not science. I repeat - it's no more than an obvious metaphor. It takes energy to do things; to resist forces. That does not mean those forces are "negative energy". At best, Hawnikg's waffle merely means inertial mass is equivalent to gravitational mass, and we arrive at Einstein's GR - not the need to postulate "negative energy". There is no definitve rubric to how a scientist or any other professional is ranked, if that's what you're asking. Other than the general reputation a community holds one of its members in - what is generally said of him, what that community's awards and prizes conferred might be, what are his achievements and how they are esteemed. That's all the validity there is. If Horizon can find leading physicists to go on air and agree that Hawking is not particularly esteemed, then there's a very good chance, especially considering his particular sensitive condition, that he's not. His institutional awards are mediocre, outside of the hermetic bubble that's Cambridge. His achievements are concerned with a very specific part of esoteric theoretical physics - interesting, no doubt, but by no means transformative of our understanding. He's written a bestselling popular science book - bestselling, somehow, because it's virtually unreadable. Not because it's too difficult to understand, but because he is a very poor writer (and that's putting the best possible gloss on it.) It wasn't an argument. It was a statement of fact. It didn't need "supporting", unless anyone was ignorant enough to suppose it wasn't true. I had already told you where to find an authoritative statement of the history of the matter. If you were rude and arrogant enough to suppose I was lying rather than you were simply ill-informed, and thus avoided the rational and polite and educative recourse of educating yourself by a simple google, then you have no one but yourself to chastise. Impossible to tell - and irrelevant to the argument you were attempting to make. Dirac was possibly the best informed physicist in the West of what was happening in Russian physics - he made several visits there, and had very close friends in their otherwise hermetically sealed community. That he predicted the positron through a mathematical implication alone is of course entirely possible - it's not that huge a leap of the imagination. As I said, it had already been made by Zollner on purely metaphysical grounds decades before, and it was known that it was a permissable solution to Einstein's field equations. As to whether Dirac's understanding of "the positron" equates to what we now take "anti-matter" to mean is another question: no one in today's physics community would think so, that's for sure. Based on what? And what on earth leads you to jump to the conclusion that "the full nature" of these (or any other) particles has been elucidated? They have not. As I've pointed out to you twice, whether the positron or any other anti-matter interacts "negatively" to a gravitational field is still completely unknown. That's fundamental, is it not? Then no modern physics (all physics) is considered "solved". I would not disagree with that - merely your reasons for saying it. Ultimately, a mathematical formulataion explains nothing. You first have to explain what the formulation means. Then you understand; then the question is solved. Not through mathematics, but through understanding: "seeing" that so and so must be so. The understanding comes first and last - the maths is just the scaffold. We do not understand through maths, as Penrose has demonstrated: we understand mathematical truths even when they're unprovable (undecidable) in the Turing/Church sense; and we can do so instantaneously. Logic, that is, is deeper and more fundamental than maths. I repeat - taken literally, that's a senseless statement. And historically, it's plain false. And that's my point. You apparently wish to claim the extreme positivist position that science is entirely about being able to predict behaviour. Well - maybe, if that situation ever arises (it hasn't yet - certainly not in quantum mechanics) - but when it does, no one will say, we undersdtand this situation perfectly now because the mathematics allows us to predict exactly what will happen. They will say, we understand this situation perfectly because this and only this happens, and our mathematics allows us to specify it at precise and perfect detail. The maths is a description; the understanding is an explanation.
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Post by abacus9900 on Oct 15, 2014 11:50:26 GMT 1
It seems to me that "negative energy" is still energy in respect of defining something that actually exists and so too in the case of "positive energy". However, to then produce a mathematical device that appears to say zero energy results as a consequence of these two is highly misleading because it is stating no energy whatever exists, which is wrong. In point of fact, positive and negative energy co-exist but balance one another, which is a more accurate interpretation of the actual situation.
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Post by mrsonde on Oct 16, 2014 12:04:34 GMT 1
It seems to me that "negative energy" is still energy in respect of defining something that actually exists and so too in the case of "positive energy". However, to then produce a mathematical device that appears to say zero energy results as a consequence of these two is highly misleading because it is stating no energy whatever exists, which is wrong. In point of fact, positive and negative energy co-exist but balance one another, which is a more accurate interpretation of the actual situation. A more accurate interpretation of the actual situation is that the presence of mass distorts the gravitational field. That's it - that's all it means.
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Post by abacus9900 on Oct 16, 2014 13:30:00 GMT 1
Well, ok, I'll take your word for that as I'm no scientist.
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Post by Progenitor A on Feb 11, 2015 15:00:18 GMT 1
Imagine a body that is at rest an infinite distance from any other body.It has zero kinetic and potential energy By the defintion of potential energy , it surely has infinite potential energy This is simply demonstrable by calculating the energy necessary to move one body an infinite distance away from another body . Now say that anther body comes close to the first body. Gravity causes them to move towards each other. The first body gains kinetic energy. As the sum of the kinetic and potential energy must be constant this means that the potential energy must become negative. Or , conversely the kinetic energy is negative A more general explanation is that there is no absolute measure of potential energy - an arbitrary point for zero potential energy has to be chosen and this is normally chosen to be at infinity for gravitational potential energy. Absolutely wrong! At an infinite distance between masses, the potential energy is infinite as shown above But what does this explain anyway? Another point to consider is what the potential energy would be if two masses were at the same point (impossible in reality of course except maybe black holes?). This would create an infinite gravitational force. Yes but infinities should really be avoided in physics To separate them to infinity would require an infinite input of energy. To separate any two bodies that are separated by less than infinity to infinity would require infinite energy! Therefore the gravitational potential energy when they were theoretically at the same point must have been minus infinity. A non-physics concept of course In other words, wherever you chose to define zero potential energy it will always become negative at some point. It is extremely dangerous to draw conclusions from infinities. By definition physics breaks down and no-one knows what they are speaking about! You are talking meta-physics
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Post by nickrr on Feb 21, 2015 15:42:02 GMT 1
Here's a definition of potential energy from Wikipedia (I found various other similar definitions): If two bodies are an infinite distance apart then there will be no force field from one to act on the other so there can be no potential energy due to the position of one in the other's field. Another way to look at it. Say we launch a rocket to greater than the earth's escape velocity and then turn it's engine off so that no more energy is given to the rocket. At that point it has a certain finite kinetic energy due to it's velocity. As it is travelling at above the escape velocity it will continue moving away from earth forever so if it travelled for an infinite time it would move an infinite distance from earth. As it moves further from earth some of it's kinetic energy will become potential energy but the total potential energy will never be greater than the initial (finite) kinetic energy. This clearly shows that moving one body an infinite distance from another does not take infinite energy. As shown above your comment about infinite distance equating to infinite potential energy is wrong. This is the result of searching Google for "gravitational potential energy diagrams" www.google.co.uk/?gws_rd=ssl#q=gravitational+potential+energy+diagramsIt shows various potential energy diagrams with potential energy on the y-axis and distance on the x-axis. What you will notice is that the potential energy is negative and rises with increasing distance, tending towards zero at infinite distance. This is what my comment was explaining. Physics is mostly maths and the maths requires the concept of infinity so it's a concept that we have to deal with whether we like it or not. It's a non-physical concept because it can't happen in the real world but it is a physics concept. You'll notice that in the potential energy diagrams in the link above the potential energy tends towards negative infinity as the x-axis distance tends to zero, which is what I was alluding to. It isn't dangerous to draw conclusions from infinities if you get the logic correct. Also this is nothing to do with meta-physics. It's just explaining how gravitational potential energy varies with distance - physics 101.
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Post by mrsonde on Feb 23, 2015 7:39:13 GMT 1
If two bodies are an infinite distance apart then there will be no force field from one to act on the other so there can be no potential energy due to the position of one in the other's field. According to GR, the field is operative between any masses, even if the distance separating them is infinite. This was equally the case for Newtonian gavitation - and for Leibniz and Mach for that matter. Pre-1905 Physics. As far as the rocket's inertial reference frame is concerned, it's at rest. Pre-1905 Physics. The rocket is equally correct to judge the Earth is moving away from it. Nothing therefore happens to its "energy" - no possible physical measurement could arrive at your calculation: else Special Relativity would be wrong, wouldn't it? Well, it might be, but not in the least for that reason. It clearly shows what a muddle you get into when you try to apply outdated concepts that belong in the 19th Century to modern knowledge. Physics is applied maths. Maths uses infinities, and lots of other concepts with no apparent physical application: Nay is quite right, Physics goes to great lengths to avoid them (renormalisation.) If it didn't, most of modern Physical theory would never have been formulated. It isn't dangerous to draw conclusions from infinities if you get the logic correct.[/quote] The logic isn't the danger - it's applying it to Physics. In the real world, such logic doesn't work. Physics 101 circa 1890. Maybe not meta-physics, but not Physics either - History of Physics at best. [/quote]
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Post by nickrr on Feb 23, 2015 20:21:21 GMT 1
According to Newtonian gravitation force is proportional to the inverse of distance squared. I think that you'll find that anything divided by infinity squared is zero.
This has nothing to do with relativity and in particular your use of special relativity when acceleration is involved is invalid. The mere fact that you try to introduce relativity here suggests that you don't know what you are talking about. The basics of physics (and this stuff is about as basic as you get) didn't change when relativity was introduced.
The rocket has been accelerated. Of course something happens to it's energy. If you accelerate something it's energy increases!
The remaining points in your post are also wrong but I've spent enough time on this.
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Post by mrsonde on Feb 26, 2015 2:18:51 GMT 1
No - infinitesimally small is the only possible answer to this equation, as Newton made explicitly clear when he considered the question.
It has everything to do with relativity. You're making claims about what happens to the energy of a mass when it's moving, and using 19th Century Physics to deduce implications about what you claim is valid about what we know about the universe now. Your deductions are wrong because Physics has moved on. As for the application of SR - you stipulated the circumstance of your thought experiment. Acceleration had ceased, you stated. Therefore no possible means could be used to determine any such fanciful occurrences to that rocket's energy because of its supposed velocity - which must, of course, be rectilinear and uniform.
Oh, do shutup man! This typical tactic of yours is unbelievably tiresome! Look - the mere fact that you try to argue about what modern Physics says is the case based on deductions that absolutely depend on dynamics that became thoroughly overthrown in 1905 conclusively demonstrates - not suggests - that you're talking complete nonsense.
Of course it did! Neither is it "the basics of physics"! Maybe for you - I gather you went in your studies about as far as A-level. But look - even before Special Relativity, my objections are still completely valid. The Principle of Relativity was proposed by Galileo, and it's as "basic physics" as you can possibly get. If there was a way to measure a difference between the entirely projected notions of "kinetic" and "potential" energy caused by rectilinear movement in a gravitational field, then not only would Einstein be falsified, but so would Galileo and the whole science of Physics back to its inception. As for what would happen to you in such a bizarre universe, when you're spinning around the Sun at thousands of miles an hour, and around the centre of the Milky Way at many thousand of mph more, and rushing through our galactic cluster at hundreds of thousands of mph more, we'll leave to your 19th Century imagination.
Irrelevant. Everything in the universe has been accelerated. The point is, if it's not accelerating still, there's absolutely no means to tell. Galileo and Einstein and every other damn physicist in between.
Read your thought experiment again. Make the necessary adjustments so you make sense. Then we can continue and see if you actually have anything to say. If you change the conditions of your experiment so that the rocket is still accelerating, then still none of your points about kinetic vs potential energy apply - the increase in energy has nothing to do with either antiquated notion, but again is determined entirely by GR: and, incidentally, your objections that I shouldn't beintroducing Relativity into it become even more bizarre! Also, incidentally, your whole thought experiment collapses - an infinite acceleration and thus infinite mass, infinite time dilation and infinite space expansion are of course quite impossible, as stated explicitly by Relativity - just as Nay pointed out to you.
No points in my post are wrong. They really are basic Physics.
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Post by Progenitor A on Feb 26, 2015 11:08:53 GMT 1
According to Newtonian gravitation force is proportional to the inverse of distance squared. I think that you'll find that anything divided by infinity squared is zero. Wrong There is no such thing as 'infinity squared' (indeed is there any such thing as'infinity?'); dividing or multiplying any thing by infinity is a mathematical nonsense
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Post by Progenitor A on Feb 26, 2015 15:00:05 GMT 1
If two bodies are an infinite distance apart then there will be no force field from one to act on the other so there can be no potential energy due to the position of one in the other's field. Not quite true. There will be a infinitesimal force field between the two bodies However I accept your correction that there will not be an infinite potential energy between the two - as the bodies are pulled apart the force to be acted against (gravity) becomes less and less. until it is infinitesimal. The sum of the forces that have to be applied to separate the two bodies will be diminishing series and that can never equal infinity (what is the sum of an infinite number of infinitesimal forces Physics is mostly maths and the maths requires the concept of infinity so it's a concept that we have to deal with whether we like it or not. It is dealt with in physics by eliminatig it I believe (normalisation I think the process is called) It's a non-physical concept because it can't happen in the real world but it is a physics concept. You'll notice that in the potential energy diagrams in the link above the potential energy tends towards negative infinity as the x-axis distance tends to zero, which is what I was alluding to. But one often hears of black holes having 'infinite gravity'. Nonsense of course It isn't dangerous to draw conclusions from infinities if you get the logic correct. In mathematics, infinities are allowable. In physics they are not and it is foolish to bandy around such terminology in physics; no valid conclusions can be drawn from its usage (if you have useful physical world conclusions to draw from infinities ,I would be interested to hear them) Also this is nothing to do with meta-physics. Invoking infinities surely does [/quote]
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